Milkweed Assassin Bug

or Zelus longipes.  A beneficial insect with a scary name.  The picture shows an immature bug:  later, the distinctive black and orange markings on his back will be much larger.  These insects eat all kinds of other insects, including milkweed aphids (aphis nerii). 

Lots of people are planting milkweed for the monarch butterflies -- their larvae feed exclusively on the leaves.  Often, a bit of panic ensues when gardeners spot other insects also making use of the milkweed.  No worries!  The Milkweed Assassin Bug usually takes care of the problem without any intervention at all.

Milkweed Assassin Bugs kill by impaling victims with a piercing mouthpart and injecting a toxin that both immobilizes and begins to dissolve them.  Luckily for me, they move slowly and are therefore easy to photograph.

Yes, it's true that they will sometimes eat Monarch larvae. 

Nature, red in tooth and claw!

 

Cue the Lion King music now and thanks to Alfred, Lord Tennyson...